Apparatus and method for continuously producing investment molds



I. J. LUBALIN July 6, 1965 APPARATUS AND METHOD FOR CONTINUOUSLY PRODUCING INVESTMENT MOLDS 3 Sheets-Sheet 1 Filed Nov. 14, 1962.

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APPARATUS AND METHOD FOR CONTINUOUSLY PRODUCING INVESTMENT MOLDS Filed Nov. 14, 1962 3 Sheets-Sheet 2 FIG. 4

FIG. IO

INVENTOR.

IR W/NI L UBALM/ BY WWW l. J. LUBALIN 3,192,580

APPARATUS AND METHOD FOR CONTINUOUSLY PRODUCING INVESTMENT MOLDS July 6, 1965 3 Sheets-Sheet 5 Filed NOV. 14, 1962 INVENTOR.

IRW/NJL UBAL/N United States Patent 3,192,589 APPARATUS AND METHOD F03 CUNTINUQIELY PRGDUQlNG INVESTMENT MGLDS Irwin I. Luhaiin, Rockviile Centre, N.Y., assignor to British Industries Corp, Avnet-Shaw Division, Plainview, Long Island, N.Y., a corporation of New York Filed Nov. '14, 1962, Ser. No. 237,684 15 (Ziaims. (Cl. 2221) The invention relates to a method of and an installation or assembly for continually producing investment casting molds or shells, in particular molds made of a rapidly hardening ceramic molding composition.

It is a broad object of the invention to provide a novel and improved method and installation of the general kind above referred to in which all the operations required to produce a casting mold are integrated in a sequential order and which will produce finished molds in continuous operation.

A more specific object of the invention is to provide a novel and improved installation of the general kind above referred to in which successive mold dies are sequentially guided past a plurality of die processing stations, and in which molds ready for casting are finished as each dies completes an ope-rationalcycle.

Another more specific object of the invention is to provide a novel and improved installation of the general kind above referred to in which positioning of the dies, charging thereof with a mold forming hardening slurry, removal of a finished mold, cleaning of the dies and readying the same for forming a new mold are automatically effected, and in which sufficient setting and hardening time for the slurry is provided within each operational cycle.

Still another more specific object of the invention is to provide a novel and improved installation of the general kind above referred to in which the die processing stations and the slurry hardening and setting stations are all disposed on a turntable and stationarily adjacent thereto, thereby reducing the floor space required to produce a continuous flow of finished molds to a minimum and also facilitating servicing of the installation.

Other and further objects, features and advantages of the invention will be pointed out hereinafter and set forth in the appended claims forming part of the application.

In the accompanying drawing several preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

In the drawing:

FIG. 1 is a perspective view of an object to be cast.

FIG. 2 is a sectional view of a mold or shell for casting the object of FIG. 1.

FIG. 3 is a sectional view of a die for casting a part of the mold according to FIG. 2. 7

FIG. 4 shows spraying of the die of FIG. 3 with a parting agent.

FIG. 5 shows filling of the die with slurry.

FIG. 6 shows means for removal of a finished mold from a die part during a preliminary stage of the mold removal. 7

FIG. 7 shows the removal means of FIG. 6 in the position in which the mold is dislodged from the die part.

FIG. 8 shows a modification of the means for dislodging a finished mold from a die part.

FIG. 9 shows another modification of the means for dislodging the finished mold.

1G. 10 shows still another means for dislodging the finished mold.

FIG. 11 is a diagrammatic plan view of an installation or assembly according to the invention, and

FIG. 12 shows diagrammatically the installation of FIG. 11 developed in a straight line.

' naphtha or other suitable agent.

3,192,580 Patented July 6, 1965 Referring now to the figures in detail, FIG. 1 shows an object to be cast exemplified as a bevel gear casting 1 before drilling and hobbing.

FIG. 2 shows the mold for casting such gear. The mold is shown as comprising a cope 12 and a drag 11.

The purpose of the installation as exemplified is to make in continuous ope-ration molds or shells for casting the gear. of FIG. 1 and more specifically the drag 11 of the mold. Accordingly, the drag 11 will be considered as the object to be cast from this point on.

FIG. 3 shows a die 15 for casting object 11. The die is a two-part die comprising a cope 10 and a drag 13 defining a mold cavity 1 1a corresponding to object '11. A sprue 14 is formed in the top Wall of cope 10 and grab fingers or pins 28 mounted on a common assembly or support plate 25 extend slidably through the top wall of cope 1t} and into the mold cavity for a purpose which will be more fully explained hereinafter.

As is evident, a mold or shell forming operation involves basically investing or filling a closed die with a suitable slurry such as a suspension of ceramic powder in a gellable silicate binder, letting the slurry set and harden, opening the die, removing the hard mold from the die and readying the die for the next mold forming operation. Slurries suitable for the purpose are described, for instance in U.S. Patents 2,795,022 and 2,811,760. In addition, several secondary or auxiliary operations are necessary or at least advisable, such as cleaning the die after each removal of a harden-ed green mold, coating the die with a parting agent, drying the die, etc.

In FIGURE 4 the spraying station comprises a pipe 49 terminating in a spray head or nozzle 51}. Pipe 43 should be visualized as being suitably connected to a supply of a parting agent such as a mixture of a silicone oil with The pipe is telescoped in a pressure air cylinder 51 by means of which the spray head may be moved into the spraying position of FIG. 1 or withdrawn to be clear of the die after completion of the spraying operation. Pneumatic or hydraulic pressure means including a cylinder and a plunger capable of imparting such motions to pipe 49 and the control of such means are well known in the art and any conventional system suitable for the purpose may be used.

The spraying components of the station are stationarily mounted at a suitable location as will be more fully explained hereinafter.

FIG. 5 shows the station for filling a die after being closed and coated with the spraying agent, with the slurry. The slurry is fed into the mold cavity 11a through sprue 14 which leaves sufiicient space to permit escape of the displaced air from the mold cavity. A valve 56 is pro vided to turn on and off the flow of the slurry. Feed pipe 26 is moved into and out of its filling position, that is, into a position aligned with sprue 14 by an air cylinder plunger system 55, as has been described in connection with FIG. 4. Pipe 263 and the air cylinder-plunger system coacting therewith are mounted stationa-rily as will be also more fully described hereinafter.

As is evident, a mold 111) corresponding in configuration to drag 11 of FIG. 2 will be formed in mold cavity 11a by the slurry hardening therein, and FIGS. 6 and 7 show the station for removing the hardening green mold from the die.

Coating of the inner wall surfaces of the die with the parting agent as described in connection with FIG. 4 facilitates on one hand a removal of the finished mold from the die without damage to the wall surfaces of the mold and on the other hand forms a vacuum seal between the mold and the inner wall surfaces of the die which must be broken when the mold is to be removed. To efiect removal of the mold from the die the cope thereof 3 is first lifted from the drag which is secured to a turntable as will be described hereinafter. FIGS. 6 and 7 show the cope in its lifted position, the means for effecting such lifting will be more fully described later on. The mold is pulled oil the drag of the die when the cope is lifted, but remains in the cope partly due to the aforementioned vacuum seal caused by the action of the parting agent and partly by engagement with grab pins 28 which extend slidably through the top Wall of the cope and into the mold cavity and hence become embedded in the slurry when the die is filled. The grab pins may terminate in a hook 23a to increase the strength with which the grab pins are anchored in the mold. The grab pins and the assembly plate 25 occupy the position shown in FIG. 6.

Removal of the mold in the station according to FIGS. 6 and 7 is aifected by means of a strikeplate 24 which is movable from the position of FIG. 6 in which it is raised above assembly plate 25, or in any event from a position in which the strike plate does not exert a downward pressure upon the assembly plate into the position of FIG. 7 in which assembly plate 25 and with it rab pins 28 are forced downwardly. The downward move ment of the grab pins may be efiected by an air cylinderplunger system 58 of conventional design.

The downward movement of pins 28 breaks the holding force of the parting agent and the mold 11b is now suspended from the grab pins only. The holding force of the grab pins is not sufiicient to support the weight of the mold so that the same will be torn loose from the grab pins and fall upon a removal arm 42. This arm constitutes part of the station shown in FIG. 6 and is pushed between cope 10 and the respective drag prior to the operation of an air cylinder-plunger system 58 to catch the mold as it breaks loose from grab pins 28. After receiving the mold, arm 42 is withdrawn with the mold thereon to deliver the same to a suitable removal belt. The arm 42 may also be stationarily mounted and a mold resting upon the same may be pushed upon a removal belt by the plunger 57a of an air cylinder system 57 as is indicated in FIG. 11 to be more fully described later on.

Instead of forcing the hardened mold out of the raised cope by mechanical means as shown in FIGS. 6 and 7, the grip of the parting agent may also be loosened by other means.

FIG. 8 shows a cope 19a formed with a jacket 1011 through which a hot liquid is conducted to soften the hardening agent.

The same result can be obtained by embedding electric heating elements 160 in a cope 10d as is shown in FIG. 9.

FIG. 10 shows an arrangement in which cope 10 is subjected to vibrations by means of a suitable and conventional vibratory device 69. The vibratory device comprises a plate in 69a formed with a suitable opening to permit passage of the loosened mold 115. The plate is vibrated by a cam arrangement 6% driven by a motor 690. Vibratory systems of this kind are well known and a more detailed description thereof does not appear to be essential for the understanding of the invention.

FIG. 11 is a diagrammatic plan view of the installation incorporating aforedescribed stations and other stations which will be more fully described hereinafter.

The installation comprises a turntable 23 rotatably' mounted above a stationary table 23a. The turntable is shown as accommodating eighteen dies. The drag 13 of each die is secured to the table and the cope 1% of each die is also supported onthe table but vertically of providing sufiicient time to elapse for the setting and hardening of the slurry in the die.

In this connection it should be emphasized that the provision of eighteen stations is entirely arbitrary. A greater or smaller number of stations may be provided. Furthermore, the distribution of the working or processing stations may be different from that shown in FIG. 11 and working stations in addition to those indicated in FIG. 11 may be provided, or less working stations than shown in FIG. 11 may be used.

In FIG. 12 the circular arrangement of FIG. 11 is developed in a straight line to show elevational views of the principal working stations of FIG. 11. The station numbers 1 to 18 used in FIG. 12 correspond to the station numbers 1 to 18 used in FIG. 11.

There is provided in association with FIG. 11 a listing of the operations to which each die is or may be subjected during one revolution of turntable 23. As will be noted, application of the parting agent is listed for the first station or position and final cleaning of the die for the last station or position. However, as is evident, the order of listing is arbitrary to a certain extent. For instance, station 2 may be considered as the first station and station 1 as the last station.

Turning now to FIGS. 11 and 12 more in detail, station 1 as listed is the station shown more in detail in FIG. 4 and explained in connection with that figure.

In station 2 the cope 10 is lowered from the raised position of station l into the die-closing position. Similarly, station 15 shows the lift-ing of the cope from the dieclosing position into a raised position.

Stations 2 and 15 show in detail the structural means provided for lowering a cope upon the drag and raising the cope above the drag. These means comprise a pair of rings 26 and 27 supported by pairs of posts 29 and 30 mounted on the turntable on opposite sides of each fixed drag 13. Two pairs of latches 31, 32 are pivotally supported on rings 26 and 27 and biased by springs 33 to turn toward each other, that is, in counterclockwise and clockwise direction respectively. Turntable 23 further mounts pairs of guides 34 for each cope 10. The aforedescribed latches 31, 32 and springs 33 are provided for each of the 18 stations or positions provided on and in association with the turntable, but are shown only in connection with stations 2 and 15, for the purpose of clarity of the drawing.

Latches 31 and 32 are engageable with four bosses 35 provided on each cope. The position of the latches is controlled by solenoids 39 and 40 which when energized will cause disengagement of the latches from the bosses 36 of the respective cope. Station 15 shows the cope raised and supported in the raised position by engagement with latches 31. Similarly, the latches should be visualized to be in engagement with the bosses 36 of the copes in any other station in which the cope is raised, that is in stations 1, 16, 17 and 18.

Raising and lowering of the cope is effected in stations 2 and 15 by means of an assembly 37. This assembly comprises a generally U-shaped frame 741, the depending arms of which mount solenoids 39 and 40 for control of the pivotal positions of latches 31 and 32. The frame may occupy one of three operational positions. It is shown in stat-ion 2 in its lowermost position in full lines, and the intermediate position and the uppermost position are indicated by dotted lines. In stations 15 the frame is shown in full lines in its intermediate posit-ion and the uppermost and the lowermost position are indicated by dotted lines. The frame is movable into any one of its three operational positions by suitable pneumatic or hydraulic means indi cated at 52.

As explained previously, each cope 10 arrives in station 2 in its raised position shown for instance in station 1 and in which it is held by engagement of latches 31 and 32 with bosses 36 on the cope. As also previously explained, the cope must be moved in station 2 from its raised position into its die-closing posit-ion. To eifect such lowering of the cope a gripping assembly 71 is provided in station 2. The gripping assembly is shown as comprising two pairs of jaws 72 and 73 for coacting with bosses or lugs 33 on each cope. The jaws are pivotally suspended from frame 70 and are movable into and out of a gripping position by means of a suitable and conventional pressure means indicated at 53.

The operations performed upon a die arriving in station 2 are as follows:

Frame 70 and with it solenoids 39, 4t and jaws 72, 73 are in the uppermost position in which the solenoids are above the level of rings 26, 27 and latches 31, 32, thus permitting step by step movement of the turntable 23 on which rings 26 and 27 are supported.

Upon arrival of a cope to be lowered, frame 7 ii is moved from its uppermost position into its intermediate position (the position shown in full lines in station 15) by means of pressure system 52. The jaws 72 and 73 are closed by operating pressure means 53 to grip bosses 3t and solenoids 39 and 40 are energized to withdraw latches 31 and 32 from bosses 36. Pressure means 52 is again operated to lower frame 7 ti and with it cope 19 now supported by the jaws into the lowermost position (shown in full lines in station 2) in which the die is closed. The jaws are now opened by again operating pressure means 53; solenoids 39 and 40 are deenergized and pressure means 52 is operated to return frame 79 and with it the jaw assembly 71 into the uppermost position.

The turntable will now move one step forward to place the closed die in station 3. In this station a final adjustment of the die position is effected. There is shown in FIG. 12 an assembly 41 having arms '75 movable int-o gripping engagement with the sides of the die to adjust the position thereof and operable by a pneumatic or hydraulic pressure means indicated at 54. The linkage as sembly is normally held above the top level of the die. It is lowered into gripping engagement upon arrival of a die to be adjusted in station 3 and it is raised again after completion of the adjustment as previously described.

Instead of providing the special adjustment means 41, adjustment of the die position can also be effected by hand, in which event station 3 is left as a blank station interposed between stations 2 and 4.

Station 4 is a filling station in which the die is charged wit-h the slurry as has been described in connection with FIG. 5.

The die after being charged in station 4 is moved step by step through stations 5 through 14. No operations are performed upon the die while passing these stations. The stations are provided to give the slurry in the die sutlicient time to set and harden.

As previously pointed out, the designation of stations 5 through 14 is arbitrary. It is merely used to indicate that there should be sufiicient hardening time between the time a die leaves the filling station 4 and arrives at station 15.

In station 15 the die is opened by raising cope 10. The equipment provided for that purpose in station 15 is the same as has been described in connection with station 2. Accordingly, frame 70 and with it jaw assembly 71 is lowered from the uppermost position into the lowermost position by operating pressure means 52. The jaws 72 and 73 are then closed by operating pressure means 53 and frame 70 together with the cope is now raised into the intermediate position shown in full lines by again operating pressure means 52. In the intermediate position latches 31 and 32 automatically engage bosses 35 on the raised cope, thereby supporting the cope. Jaws 72 and 73 are now opened by operating pressure means 53 .and frame '70 is returned into its uppermost position by operating pressure means 52. The turntable and all components thereon are now free to advance one step to move the open die into station 16 in which the hardened green mold is removed from the cope and the installation as such, as has been described in connection with FIGS. 6 and 7. The

6 mold is then pushed on a removal belt by means of an air cylinder 57 supported on the central shaft shown in FIG. 11 and may be transported to a torching station for microcrazing if required.

After removal of the mold the turntable is advanced one step to bring the die into station 17 in which remaining particles of the molding material indicated at 74 are removed by brushing, blowing or other suitable means.

The die is then advanced one step into station 18 in which final cleaning of the die is effected. Cleaning means are diagrammatically indicated by a blast pipe 43. The blast pipe may be moved into and out of its working position by a pressure means indicated at 59.

Each die upon arriving in station 18 has completed an operational cycle and a new operational cycle begins when the die cleaned in station 18 is advanced into station 1. As is evident, the operation of the pressure means, blast means, circuit means, etc., hereinbefore described in con nection with an operational cycle of the turntable must be eifected in a pre-determined sequential order. There are known various cycle timing devices suitable for the pur pose. The arrangement of the cycle timing device as such does not constitute part of the invention and is hence not described in detail.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention, it will be understood by those skilled in the art after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed as new and desired to be secured by tters Patent is:

1. An installation for repeat production of investment casting molds, said installation comprising a turntable, a plurality of two-part mold dies each including a cope and a drag, the drag of each die being secured to the table for movement in unison therewith and the cope being supported on the table movable between a die-opening position in which the cope is vertically spaced apart with reference to the drag and a die-closing position, and a plurality of stations disposed circumferentially distributed about said turntable, one of said stations including means for moving the cope of each die reaching said station from the open position to the closed position, another of said stations including means for pouring into a closed die reaching said other station a rapidly hardening slurry to form a mold therein, still another station including means for vertically lifting a cope with a hardened mold therein in reference to the drag of the die into a die opening position, a further station including means for ejecting the hardened mold from its cope in the die-opening position, means insertable between the cope and die in the die-opening position to receive the ejected molds,

- and means to remove the ejected mold from the station.

2. An installation according to claim 1 wherein said plurality of stations also'comprises a station including means for cleaning the inner Wall surfaces of open dies and a station including means for applying a parting agent to inner wall surfaces of open dies.

3. An installation according to claim 1 wherein said means included in the respective stations for moving the cope and for lifting the cope are stationarily mounted adjacent to the turntable and comprise actuating members movable between a working position overhanging the table to coact with the cope of the respective die thereon and a rest position retracted from said overhanging position.

4. An installation accordin to claim 1 wherein grab pins extend slidably through a wall of each cope and into the mold cavity defined by each cope and the respective drag whereby the ends of the grab pins are embedded in slurry filling said cavity, and wherein the station for dislodging hardened molds from the raised copes comprises stationarily mounted actuating means coacting with the grab pins in each cope reaching said station to force said embedded pins deeper into the cavity thereby dislodging the mold from the cope, the weight of the dislodged mold pulling the same free of the grab pins.

' 5. An installation according to claim 4 wherein said grab pins are mounted on a common support member, and wherein saidactuating means comprise a strike plate engageable with said support member to displace the same toward the cope thereby pushing the embedded grab pins deeper into the cavity for the purpose of pushing the mold out of the cope.

6. An installation according to claim 1 wherein the means for moving and lifting the cope include a U- shaped frame, pivotable latches mounted on the turntable, spring-biased to turn toward each other, and adapted to engage bosses on the cope; means to disengage the latches from the cope; pivotable jaws on the frame adapted to grip lugs on the cope, means to move the jaws into and out of a gripping position; guides for vertically raising and lowering the cope, and means to move the U frame vertically to effect the lowering and raising of the cope by the engagement and disengagement of the latches and jaws on the bosses and lugs of the cope.

7. An installation according to claim 1 wherein the means for investing the closed die includes a feed pipe connected to a slurry source, means to control the flow of slurry through the feed pipe, means to place the feed pipe in registry above the sprue opening of the closed die to permit the filling of the die and to remove the feed pipe after said investing is completed.

8. An installation according to claim 1 wherein the means to receive and remove the hardened mold includes: a removal arm insertable between the cope and the drag prior to and during the ejection of the hardened mold from the cope; a conveying means adjacent to the removal arm, and means to transfer the hardened mold from the removal arm to the conveying means.

9. An installation for repeat production of investment casting molds, said installation comprising a turntable, a plurality of two-part mold dies, each including a cope and a drag, the drag of each die being secured to the table for movement in unison therewith and the cope being supported on the table movable between a die-opening position in which the cope is vertically spaced apart with reference to the drag and a die-closing position, and a plurality of stations stationarily disposed in circumferentially spaced relationship about said turntable to be passed by each die during one revolution of the turntable, said stations including means coacting with each die as the die passes the respective station for sequentially flushing a die in a die-opening position, applying an inner parting agent to the inner wall surfaces of the die, vertically moving the cope onto the drag and into a die-closing position, pouring a rapidly hardening ceramic slurry into the closed die to form a mold, vertically lifting the cope of the die with the mold therein into a die-opening position, ejecting the hardened mold from the cope into a removal arm inserted beneath the cope and thereafter removing the arm and the hardened mold.

10. An installation according to claim 9 wherein the station including means for pouring with the slurry and the station including means for opening an invested die are circumferentially spaced in reference to each other by a distance providing a travel time for each invested die sufficient to permit hardening of the slurry in the die.

11. The method of continually producing investment casting molds by means of dies, each having a cope and a drag, the drag of each die being secured to a turntable for movement in unison therewith, and the cope being movable between a die-opening and a die-closing posi tion, said method comprising the steps of:

cycling a plurality of dies step-by-step along a closed path of the table;

pouring 'amoid-forming, hardening slurry into' suc cessive dies in predetermined die-closing positions along said path;

causing the dies to travel through a predetermined distance along said path for a time sufiicient to provide for hardening of the slurry;

vertically lifting the copes of successive dies with a hardened mold therein with reference to the drag of the dies to a die-opening position;

inserting between the copes and the drags in the dieopening position a mold receiving means;

ejecting the hardened molds from successive copes of open dies onto the receiving means;

removing the hardened molds and the receiving means from successive dies in the die-opening position; and

vertically lowering the copes upon the drags of successive dies to a die-closing position for starting a new cycle.

12. The method of continually producing investment casting molds by means of dies, each having a cope and a drag, the drag of each die being secured to a turntable for movement in unison therewith, and the cope being movable between a die-opening and a die-closing position,

said method comprising the steps of:

cycling a plurality of dies step-by-step along a closed path of the table; pouring a mold-forming, hardening slurry into successive dies in predetermined die-closing positions along said path;

causing the dies to travel through a predetermined distance along said path for a time sufficient to provide for hardening of the slurry;

vertically lifting the copes of successive dies with a hardened mold therein with reference to the drag of the dies to a die-opening position;

inserting between the copes and the drags in the dieopening position a mold receiving means;

ejecting the hardened molds from successive copes of open dies onto the receiving means;

removing the hardened molds and the receiving means from successive dies in the die-opening position; then flushing the inner walls of successive open dies to remove debris therefrom;

then spraying the inner walls of successive open dies with a parting agent; and

finally lowering the copes upon the drags of successive dies to reclose the dies for starting a new cycle.

13. The method according to claim 12 wherein the parting agent is sprayed by inserting a spray head attached to a feed conduit between the successive copes and drags in a die-opening position;

spraying the inner walls of successive dies by passing the parting agentthrough the feed pipe and spray head; and V withdrawing the spray head and feed pipe.

14. The method of continually producing investment casting molds by means of dies, each having a cope and a drag, the drag of each die being secured to a turntable for movement in unison therewith, and the cope being movable between a die-opening and a die-closing position, said method comprising the steps of;

cycling a plurality of dies step-by-step along a closed path of the table; locating a feedpipe in registry above the sprue opening of successive dies; pouring a mold-forming, rapidly hardening ceramic slurry into successive dies through the feed pipe, the dies being in a predetermined die-closing position along said closed path; causing the dies to travel through a predetermined distance along said path for a time suflicient to provide for hardening of the slurry; vertically raising the copes of successive'dies containing a hardened mold therein by means of gripping bosses on the copes to a die-opening position, the copes being vertically spaced apart with reference to the drags;

placing between the copes and drags a removal arm to receive the hardened mold from the copes;

ejecting the hardened molds from successive copes in the die-opening position onto the removal arm;

removing the hardened molds from the removal arm;

withdrawing the removal arm from between the successive copes and drags; and

vertically lowering the copes upon the drags of successive dies by means of gripping bosses on the copes to a die-closing position for starting a new cycle.

15. An installation for repeat production of investment casting molds, said installation comprising:

a turntable;

a plurality of dies, each including a cope element and a drag element, the drag element being secured in a stationary position on the table for rotary movement in unison therewith and the cope element being supported on the table and vertically movable with reference to the stationary drag element between a die opening position and a die closing position;

and a plurality of stations disposed circumferentially about the turntable, said stations including means for filling a hardening slurry into successive dies in a die closing position,

means for placing the successive dies in a die opening and die closing position,

means for ejecting a hardened mold from the cope element of successive dies in a die opening position and means for removing the ejected molds.

References Cited by the Examiner UNITED STATES PATENTS 1,3 51,020 8/20 Brady 22-25 2,6 80,270 6/54 Gedris 2225 2,783,509 3/57 Miller 2221 2,832,107 4/58 Weaver 2221 2,843,892 7/58 Sager et a1 2234 2,873,475 2/59 Linhorst 184 2,956,321 10/60 Halward 22-94 2,973,555 3/61 Schwepke 1820 3,059,294 10/ 62 Dunn et a1. 2221 3,096,547 7/63 Hunter et al. 2236 3,102,304 9/ 63 Divers 18-20 MARCUS U. LYONS, Primary Examiner.

MICHAEL V. BRINDISI, Examiner. 

1. AN INSTALLATION FOR REPEAT PRODUCTION OF INVESTMENT CASTING MOLDS, SAID INSTALLATION COMPRISING A TURNTABLE, A PLURALITY OF TWO-PART MOLD DIES EACH INCLUDING A COPE AND A DRAG, THE DRAG OF EACH DIE BEING SECURED TO THE TABLE FOR MOVEMENT IN UNISON THEREWITH AND THE COPE BEING SUPPORTED ON THE TABLE MOVABLE BETWEEN A DIE-OPENING POSITION IN WHICH THE COPE IS VERTICALLY SPACED APART WITH REFERENCE TO THE DRAG AND A DIE-CLOSING POSITION, AND A PLURALITY OF STATIONS CIRCUMFERENTIALLY DISTRIBUTED ABOUT SAID TURNTABLE, ONE OF SAID STATIONS INCLUDING MEANS FOR MOVING THE COPE OF EACH DIE REACHING SAID STATION FROM THE OPEN POSITION TO THE CLOSED POSITION, ANOTHER OF SAID STATIONS INCLUDING MEANS FOR POURING INTO A CLOSED DIE REACHING SAID OTHER STATION A RAPIDLY HARDENING SLURRY TO FORM A MOLD THEREIN, STILL ANOTHER STATION INCLUDING MEANS FOR VERTICALLY LIFTING A COPE WITH A HARDENED MOLD THEREIN IN REFERENCE TO THE DRAG OF THE DIE INTO A DIE OPENING POSITION, A FURTHER STATION INCLUDING MEANS FOR EJECTING THE HARDENED MOLD FROM ITS COPE IN THE DIE-OPENING POSITION, MEANS INSERTABLE BETWEEN THE COPE AND DIE IN THE DIE-OPENING POSITION TO RECEIVE THE EJECTED MOLDS, AND MEANS TO REMOVE THE EJECTED MOLD FROM THE STATION. 